The luxury automaker emailed Model S owners to say it received a complaint recently from an owner in Europe, and were issuing a voluntary safety check to address possible malfunctions. The seatbelt has not been the source of any injuries, the company said, and no similar event has been recorded in Australia.

Palo Alto-based Tesla has earned solid ratings for its vehicle safety features. The American National Highway Traffic Safety Administration has given the Model S its highest rating - 5-stars - for overall safety annually since 2013.

However, Consumer Reports magazine last month downgraded the overall reliability rating of the Model S, citing repair issues with early vehicles. The problems ranged from body rattles to drive train and power equipment repairs. CEO Elon Musk said this month many of those problems have been fixed.

The latest recall is to address a front seatbelt that may be improperly secured, according to the company email. The rear seat belts are not a concern.

The company found the problem in one vehicle in Europe, and checked more than 3,000 other vehicles for the same problem.

"This is the only customer vehicle we know of with this condition," the company said.

"This vehicle was not involved in a crash and there were no injuries," the letter said. "However, in the event of a crash, a seat belt in this condition would not provide full protection."

Tesla has recalled some Model S vehicles since introducing the car in 2012. Tesla alerted owners in 2014 to potential overheating during recharging, according to records filed with NHTSA. The company solved the problem through wireless software upgrades and new charging adapters with thermal fuses.

It's also not the first time Tesla has recalled a vehicle based on a single complaint. The company launched a voluntary safety check in 2010 for Roadster models after an electrical short led to a possible fire behind a headlamp in one car.

Ben Kallo, an analyst for Robert W. Baird in San Francisco, said the company has built its reputation on high quality, safe luxury sedans. The recall is "par for the course about how seriously they take safety," he said.

Part of the marketing for Tesla has been to build strong relationships with owners, Kallo said. The recall, which he sees as a minor issue, helps bolster their image as a company that quickly responds to its customers. "Forget about being an electric vehicle," Kallo said. "You want to be the safest car on the road."

The recall comes as the company is driving hard to ramp up production at its Fremont factory for the new line of Model X SUVs. The crossover, based on the Model S design, is expected to get high safety scores. Tesla has added several new features, including a camera, radar and sonar sensors, to help drivers avoid collisions.